1. Field of the Invention
Embodiments of the invention relate to the field of nanotechnology, and more specifically, to carbon nanotubes.
2. Description of Related Art
Mechanical and structural reliability in semiconductor packages have become important due to increased circuit densities, power dissipation, and die size. One factor in packaging reliability is the stresses caused by mismatches between the coefficients of thermal expansion (CTEs) of the package and the semiconductor die. High level of heat dissipation and the mechanical loadings of the package mounted on a circuit board are additional sources of these stresses. It is, therefore, useful to have sensors that may measure the stress level on the packages.
Existing techniques for sensing stresses on packages have a number of disadvantages. One technique uses strain gauges to measure strain. These gauges are usually cemented on the package. This technique may lead to damage to the element or elements to which the gauges are cemented. Another technique uses silicon piezo-resistive stress sensors integrated with the process flow. This technique has not been mature enough for semiconductor packaging. Currently, there is no technique to measure the build-up of in-situ stress or state of stress in a package without destructive testing.